Related papers: Recoiling supermassive black hole in changing-look…

Radiation from the blazar class of of active galactic nuclei (AGN) exhibits fast time variability which is usually ascribed to instabilities in the emission region near the central supermassive black hole. The variability time scale is…

Powerful supermassive black hole (SMBH) winds in the form of ultra-fast outflows (UFOs) are detected in the X-ray spectra of several active galactic nuclei (AGN) seemingly independently of their radio classification between radio quiet (RQ)…

The Seyfert galaxy Markarian 590 offers a rare glimpse into the dynamic life cycle of black hole accretion, captured across multiple wavelengths from the years 1975 to 2025. Using the decade-long multi-band observations from the Swift…

Here we confirm the short periodic variability of a subparsec supermassive binary black hole (SMBBH) candidate Mrk 231 in the extended optical photometric data set collected by the Catalina Real-Time Transient Survey (CRTS) and All-Sky…

Broad Balmer emission lines in active galactic nuclei (AGN) may display dramatic changes in amplitude, even disappearance and re-appearance in some sources. As a nearby galaxy at a redshift of z = 0.0264, Mrk 590 suffered such a cycle of…

Tidal disruption events (TDEs) as excellent beacons to black hole (BH) accreting systems have been studied for more than five decades with a single star tidally disrupted by a central massive BH. However, if considering two stars passing…

We present SDSSJ092712.65+294344.0 as the best candidate to date for a recoiling supermassive black hole (SMBH). SDSSJ0927+2943 shows an exceptional optical emission-line spectrum with two sets of emission lines: one set of very narrow…

The X-ray spectrum of GRS 1915+105 is known to have a ``broad iron spectral feature'' in the spectral hard state. Similar spectral features are often observed in Active Galactic Nuclei (AGNs) and other black-hole binaries (BHBs), and…

We present the results of a 500 ksec long XMM-Newton observation and a 120 ksec long quasi-simultaneous Chandra observation of the Narrow Line Seyfert 1 galaxy 1H0707-495 performed in 2010 September. Consistent with earlier results by…

The spin is an important but poorly constrained parameter for describing supermassive black holes (SMBHs). Using the continuity equation of SMBH number density, we explicitly obtain the mass-dependent cosmological evolution of the radiative…

We report the discovery of a relativistic jet in Mrk~110, a narrow-line Seyfert 1 galaxy historically classified as a radio-quiet active galactic nucleus (AGN). Very Long Baseline Interferometry (VLBI) observations reveal intermittent jet…

To understand the mass distribution and co-evolution of supermassive black holes with their host galaxy, it is crucial to measure the black hole mass of AGN. Reverberation mapping is a unique tool to estimate the black hole masses in AGN.…

A strong X-ray outburst was detected in HE1136-2304 in 2014. Accompanying optical spectra revealed that the spectral type has changed from a nearly Seyfert 2 type (1.95), classified by spectra taken 10 and 20 years ago, to a Seyfert 1.5 in…

Powering the 10^62 erg nuclear outburst in the MS0735.6+7421 cluster central galaxy by accretion implies that its supermassive black hole (SMBH) grew by ~6x10^8 solar masses over the past 100 Myr. We place upper limits on the amount of cold…

Theory predicts that a supermassive black hole binary (SMBHB) could be observed as a luminous active galactic nucleus (AGN) that periodically varies on the order of its orbital timescale. In X-rays, periodic variations could be caused by…

We analyse the spectra of the archival XMM-Newton data of the Seyfert 1 AGN Zw 229.015 in the energy range $0.3 - 10.0$ keV. When fitted with a simple power-law, the spectrum shows signatures of weak soft excess below 1.0 keV. We find that…

The spectra of Active Galactic Nuclei (AGNs) are often characterized by a wealth of emission lines with different profiles and intensity ratios that led to a complicated classification. Their electro-magnetic radiation spans more than 10…

There is general consensus that active galactic nuclei (AGNs) derive their radiating power from a supermassive black hole (SMBH) that accretes matter. Yet, their precise powering mechanisms and the resulting growth of the SMBH are poorly…

The structure of the accretion flow onto supermassive black holes (SMBH) is not well understood. Standard disc models match to zeroth order in predicting substantial energy dissipation within optically-thick material producing a…

In this Letter, we report a potential candidate of recoiling supermassive black hole (rSMBH) in SDSS J1619 based on similar velocity shifts and line widths of the blue-shifted broad components in H$\alpha$ and [O~{\sc iii}] doublet. The…